This invention relates generally to control circuitry for automatically controlling the level of sound recording and particularly to such control circuitry for use in sound movie cameras.
In the past, movie cameras have been provided with means for recording the sound associated with simultaneously recorded video. Such cameras typically include an automatic sound level control circuit which causes sounds of different intensities to be amplified and recorded in inverse proportion to their respective intensities. That is, low intensity sounds are amplified to a greater extent than higher intensity sounds so that all reproduced sounds have similar intensities.
A drawback associated with such controls is that, in the absence of a desired sound such as human speech, low intensity background noises are greatly amplified and reproduced at an undesirably high intensity.